Xbox Live went down for many users on Sunday, the game network's second outage in the past few days. Xbox Live users turned to Twitter to complain that they were unable to play games online or access other content.
The Xbox Live support status website also appeared to be offline, displaying only the Xbox logo with a churning circle.
Microsoft said it was aware of the situation and was investigating the cause.
"We understand some users may be experiencing errors with sign in or matching making on Xbox Live, and are currently investigating," Xbox Support said in a tweet. "Please check back here for details."
It's the second outage for the game-play network in the past three days. A similar outage struck players on Thursday.